The major discovery this year are as follows. 1. Showed that radiation attenuated sporozoites administered intravenously into NHP induced potent CD4 and CD8+ T cell responses in blood and liver. Established that a high frequency of NK cells in the liver secrete IFN-g in response to stimulation providing an additional effector cell for protection. Furthermore, showed that monocytes and dendritic cells present SPZ antigen to T cells. 2. Demonstrated that a novel full length P. falciparum CSP protein elicited potent CD4+ T cell and humoral immunity in mice sufficient to limit parasite replication in vivo following challenge. 3. Initiated a phase I clinical trial assessing whether irradiated PfSPZ given by the IV route is safe and protective in a dose escalation study.